Compact internal window air conditioner

ABSTRACT

A Compact Internal Window Air Conditioner (CIWAC) whose casing is adapted to be supported inside the room on the internal windowsill of a horizontally-sliding-pane window. In its installed state, the CIWAC does not interfere with the operation of the sliding windowpane. Further, the CIWAC comprises flexible sliding seals, which sealingly contact the sliding windowpane to reduce the cross-leakage of room-air and outside air. Height-adjustable pedestals are provided to further support the CIWAC from the floor. An electronic noise cancellation system is also provided to reduce the noise generated by the CIWAC during its operation. The CIWAC is relatively inexpensive to manufacture and does not need a wall-opening or modifications to the window for installation. Therefore, the CIWAC can be easily installed or uninstalled.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from U.S. provisional patent application No. 60/565,242 filed on Apr. 23, 2004.

BACKGROUND OF THE INVENTION

The present invention relates to air-conditioners and more particularly to window-mounted air-conditioners. The present invention can also be used with window-mounted heat-pumps and de-humidifiers.

Commercially available window air-conditioners (WACs) are generally designed for use with vertically-sliding windows. As an example, the commercially available Samsung™ Model No. AW0505M WAC is quite representative of the design of such WACs. However, modern homes and apartment buildings are increasingly being fitted with horizontal sliding windows. Most commercially available WACs are designed for vertically-sliding windows, such as single-hung or double-hung windows. Therefore, they are relatively wider compared to their height or depth. Further, a major portion of their casing has to be located outside the room for the circulation of the outside air over their condenser coils. Therefore, commercially available WACs cannot easily be fitted in modern horizontal sliding windows without major modifications to the window. Further, a window, which is modified for the installation of a WAC, generally cannot be easily opened for cross-ventilation with outside air if required. Yet further, the modified window cannot be closed if required for personal safety. Thereby the safety of the room's occupant and possessions is greatly reduced by such an installation. Yet further, a WAC thus installed may be stolen because it can be accessed from outside the room.

For the above reasons and to avoid modification to the horizontal sliding window and to maintain the full operability of the horizontal-sliding window, the WAC is alternately installed in an opening in the wall. The provision of the opening in the wall greatly increases the labor and cost for installing the WAC. In many cases, the cost of installation of the WAC may exceed the purchase price of the WAC, which can be as low as $60 per unit. If the room's occupant is a renter, he/she may not be allowed to make modifications to the window or the wall to install the WAC. Thus it is almost impossible for such occupants to install a WAC to achieve a more comfortable living environment.

Portable air-conditioners, for example, the Maytag™ 9,000 BTU Portable Air Conditioner, are marketed to meet the requirements of such users. The portable air-conditioners are refrigeration units on rolling casters, which use a flexible air hose for evacuating the rejected heat as warm air. The free end of the flexible hose can be mounted on an open window for expelling the warm air to the outside environment. However, these portable air-conditioners are relatively expensive. For example, the Maytag™ 9000 BTU Portable Air Conditioner currently sells for $499 per unit. Thus, portable air conditioners are not a viable solution for most potential users of WACs.

There have be no commercial attempts to market a WAC which easily fits a horizontal sliding window, is relatively inexpensive, is easy to install, is compact, can be easily relocated, and maintains the full operability of the window.

The WAC of the present invention attempts to provide all these user-friendly features.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a Compact Internal Window Air Conditioner (CIWAC) whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted totally inside the room on the inside windowsill of a horizontally-sliding-pane window is disclosed.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window without interference to the operation of the horizontally-sliding-windowpane is disclosed.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises flexible air-seals, which slidingly contact the inside surface of the windowpane of the horizontally-sliding-pane window.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises flexible air seals, which are installed on the inside surface of the windowpane of the horizontally-sliding-pane window and slidingly contact the rear panel of the casing of the AC.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises pedestal means for supporting the CIWAC's casing from the floor.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises height-adjustable pedestal means for supporting the CIWAC's casing from the floor.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises attachment means for attaching the CIWAC's casing to an inside wall surface of the room.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC is configured for flow of the cooling air for the refrigerant condenser coil through the rear panel of the casing of the CIWAC.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC is configured such that condensed water is collected from the evaporator coil and used to cool the refrigerant condenser coil.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC is configured such that condensed water is collected from the evaporator coil and used to cool the refrigerant condenser coil by being sprayed on the refrigerant condenser coil.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC is configured such that the casing has a width “W” where “W” is less than or equal to “X” and “W” is greater than “(X−1)” where “X” is an integer denoting 6 to 24 inches.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises a refrigerant flow reversing means to enable the operation of the CIWAC as a heat-pump.

In another aspect of the present invention, a CIWAC whose casing is adapted to be mounted on the inside windowsill of a horizontally-sliding-pane window is disclosed. In this embodiment, the CIWAC further comprises an electronic noise cancellation system for reducing the noise generated during the operation of the CIWAC.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an installed isometric representation of the Compact Internal WAC (CIWAC) of the present invention showing its installation within a horizontal-sliding-pane window. As used herein, the term “pane” means the frame containing the glass, which slides within the wall-attached outer-frame of the window.

FIG. 2A is a representation of the front panel of the CIWAC, the front panel being located facing the inside of the room.

FIG. 2B is a representation of the rear panel of the CIWAC, the rear panel being located facing the outside of the window of the room.

FIG. 2C is a sectional side-elevational representation of the CIWAC of FIG. 1 showing the internal arrangement of its main components.

FIG. 3 is an exploded isometric representation of CIWAC 10 of FIG. 1 showing the internal arrangement of its main components. For purposes of clarity, side panels 20 r and 20 l are not shown in this figure.

FIG. 4 is a process flow representation of the CIWAC of FIG. 1 during its operation as an air-conditioner.

FIG. 5A is a process flow representation of the heat-pump embodiment of the CIWAC of FIG. 1 during its operation as a room-air cooler.

FIG. 5B is a process flow representation of the heat-pump embodiment of the CIWAC of FIG. 1 during its operation as a room-air heater.

FIG. 6 is a process flow representation of the CIWAC of FIG. 1, which incorporates an electronic noise cancellation system for reduction of noise generated by the CIWAC during its operation.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1, 2A, 2B, 2C, and 3, CIWAC 10 of the present invention is adapted to be mounted on the inside lower windowsill 70 s of a conventional horizontal-sliding-pane window 70.

CIWAC 10 is configured as a rectangular box-shaped casing 20 having a width dimension “W”, a height “H”, a depth “D” and a notched corner 20 c at its lower rear end. Width dimension “W” could vary between 24 and 6 inches depending on the cooling capacity of CIWAC 10 as well as other later-discussed considerations. As shown in forthcoming examples, height “H” and depth “D” could vary depending on width “W” and the cooling capacity of CIWAC 10.

Casing 20 comprises a front panel 20 f, a rear panel 20 z, a right side panel 20 r, a left side panel 201, a top panel 20 t, a bottom panel 20 b, a notched corner top panel 20 x, and a notched corner rear panel 20 y. Dimensionally, the height of 20 f equals the sum of the heights of 20 z and 20 y, or as shown in FIG. 2C, “H=H1+H2”. Dimensionally, the depth of 20 t equals the sum of the depths of 20 b and 20 x or as shown in FIG. 2C, “D=D1+D2”. The corner 20 c is dimensionally engineered for casing 20 to be seated on the ledge 701 created by lower windowsill 70 s and the room wall surface 70 w adjacent to windowsill 70 s.

Casing 20 can be made of steel or rigid polyurethane or rigid plastic or any other suitable material of construction that is used for conventional WACs. Further panels 20 f, 20 z, 20 r, 20 l, 20 t, 20 b, 20 x, and 20 y can be individual pieces that are fastened by conventional means such as screws to form casing 20. Alternatively, two or more of panels 20 f, 20 z, 20 r, 20 l, 20 t, 20 b, 20 x, and 20 y can be integrally combined to reduce the manufacturing complexity of CIWAC 10; the combined pieces can then be fastened by conventional means such as screws to form casing 20. Yet further, any or all of the panels can be insulated, internally or externally, for noise or heat-loss reduction purposes.

Front panel 20 f has a warm room-air return grill 26 i and a cooled room-air expelling grill 26 o which is located below grill 26 i. These grills can be stamp-cut into front panel 20 f or they can be removable grills that are mounted into suitable openings cut into front panel 20 f. As is customary with Window Air-Conditioners (WACs), an air-filter (not shown) can be provided in grill 26 i to remove particulate matter that may be present in the room air, which is represented by air streamline 32 in FIG. 2C.

Rear panel 20 z has an outside-air intake opening 22 i and a warmed outside-air exhaust opening 22 o which is located above 22 i. Openings 22 i and 22 o are stamp-cut into rear panel 20 z. Removable grills and air-filters can also be provided in openings 22 i and 22 o for particulate removal and safety purposes. Thus outside air, which is represented by air streamline 42 in FIG. 2C, is circulated through casing 20.

The internal volume of casing 20 is divided into a plurality of relatively gas-tight internal sub-volumes 24 z, 24 y, 24 x, 24 u, 24 v, and 24 w by internal partitions 24, 28 a, 28 b, and 28 g and blower air-outlet profile plates 29 a and 29 b. Internal partitions 24, 28 a, 28 b, and 28 g and profile plates 29 a and 29 b are located generally perpendicularly to side-panels 20 r and 20 l and have width dimensions generally equal to the internal width dimension between 20 r and 20 l. The edges of internal partitions 24, 28 a, 28 b, and 28 g and profile plates 29 a and 29 b can be welded or otherwise attached to the internal surfaces of side-panels 20 r and 20 l. Alternatively, fluid separating means such as packings, gaskets, caulking, etc. can be provided between the cutting edges of internal partitions 24, 28 a, 28 b, and 28 g and profile plates 29 a and 29 b and the internal surfaces of side-panels 20 r and 20 l to reduce air cross-leakage between sub-volumes 24 z, 24 y, 24 x, 24 u, 24 v, and 24 w.

Partition 24 has bends or folds, which give it an approximately Z-shaped longitudinal cross-section. These folds divide partition 24 into sections 24 a, 24 b, 24 c, 24 d, 24 e, and 24 f. An opening 24 p is provided in section 24 b for mounting electrical motor 40 m of blower 40 (described later herein). A similar opening 24 q is provided in section 24 d for mounting electrical motor 30 m of blower 30 (described later herein). Motors 40 m and 30 m are attached to panel sections 24 b and 24 d by screws or other suitable fasteners (not shown). Openings 29 h and 29 i are provided in profile plates 29 a and 29 b respectively for penetratingly locating air-flow outlets 40 o and 30 o of blowers (described later herein) 40 and 30 respectively.

Evaporator coil 30 c is located within sub-volume 24 u. Conventionally, evaporator coil 30 c is configured as a bank of finned tubes. However, other heat-exchanger configurations such as plate-heat-exchangers can also be used without departing from the spirit of the invention. Evaporator coil 30 c has an air-side flow face that is generally rectangular and which generally conforms dimensionally to grill 26 i. Also located in sub-volume 24 u is the impeller section 30 b of room-air circulation blower 30. Circulation blower 30 is a centrifugal type of blower whose air-flow inlet 30 i is in fluid communication with sub-volume 24 u. The air-flow outlet 30 o of blower 30 is in fluid communication with sub-volume 24 v which, in turn, is in fluid communication with room-air outlet grill 26 o in front panel 20 f. While blower 30 is shown and described as a centrifugal type of blower, it will be obvious that other air-movement devices such as fans could also be used without departing from the spirit of the invention.

Located under evaporator coil 30 c is condensed water collection pan 30 d, which collects any condensed moisture that may drip from evaporator coil 30 c during operation of CIWAC 10.

Condenser coil 40 c is located within sub-volume 24 x. Conventionally condenser coil 40 c is also configured as a bank of finned tubes. However other heat-exchanger configurations, such as plate-heat-exchangers can also be used. Condenser coil 40 c has an air-side flow face that is generally rectangular and which generally conforms dimensionally to flow opening 22 i in rear panel 20 z. Also located in sub-volume 24 x is the impeller section 40 b of outside-air circulation blower 40. Circulation blower 40 is a centrifugal type of blower whose air-flow inlet 40 i is in fluid communication with sub-volume 24 x. The air-flow outlet 40 o of impeller section 40 b is in fluid communication with sub-volume 24 y which, in turn, is in fluid communication with outside-air outlet opening 22 o in rear panel 20 z.

To provide a compact arrangement, electrical motor 30 m, which rotates the rotor of blower 30, is located in sub-volume 24 x. An opening 24 q in partition section 24 d enables motor 30 m to be installed in this location. Similarly, electrical motor 40 m, which rotates the rotor of blower 40, is located in sub-volume 24 z. An opening 24 p in partition section 24 b enables motor 40 m to be installed in this location.

A standard air-conditioner compressor unit 50 and a condensed water removal pump 30 p are located within sub-volume 24 w. As described herein, compressor unit 50 includes the impeller 50 i and motor 50 m which rotates impeller 50 i to compress the refrigerant fluid in compressor unit 50. The refrigerant fluid flows into impeller 50 i through a fluid inlet connector 50 p and flows out of impeller 50 i through a fluid outlet connector 50 q. Condensed water drain line 30 m, which is penetratingly routed through profile plate 29 b and partition sections 28 b and 28 g, connects condensed water drain pan 30 d to the water inlet connector of condensed water pump 30 p. Condensed water removal line 30 n is penetratingly routed through partition section 24 f and connects water outlet connector of condensed water pump 30 p to condensed water sprayer 30 s which is located above condenser coil 40 c. Condensed water sprayer 30 s has spray orifices 30 h, which spray the condensed water over condenser coil 40 c to provide additional cooling of the refrigerant within condenser coil 40 c by sensible cooling and evaporation. The un-evaporated condensed water is entrained by the warmed outside air 42 w (described later) and thereby removed from CIWAC 10.

Standard electrical controls (not shown) for controlling the operation of a WAC can also be located within sub-volume 24 w or in any other suitable location within casing 20. These controls include, as a minimum, electrical circuits for starting and stopping of electrical motors 30 m, 40 m, and 50 m and will be obvious to one of ordinary skill in the art. Additionally, thermocouples, thermostats, timers, and other refinements can also be provided to further enhance the operating features of CIWAC 10. All such refinements will be obvious to one of ordinary skill in the art.

Refrigerant flow conduits 50 a, 50 b, 50 c, and 50 d (shown in FIG. 4) provide the closed loop for the flow of refrigerant between compressor impeller 50 i, condenser coil 40 c, gas expansion device 50 v (described later herein), and evaporator coil 30 c.

In the following description, the refrigeration loop of FIGS. 3 and 4 operates in a simple closed-circuit, vapor-compression cycle wherein compressor impeller 50 i circulates gaseous high-pressure or 2-phase refrigerant 52 r (shown in FIG. 4) through condenser coil 40 c and condensed or low-pressure refrigerant 52 t (shown in FIG. 4) through evaporator coil 30 c. Details of the closed-circuit, vapor-compression cycle are given in standard engineering textbooks such as Mechanical Engineers Handbook, 8^(th) Edition, Chapter 19, pages 19-6 to 19-9, which are incorporated herein by reference.

Following the standard operation of an air-conditioner, operation of blower 30 induces warm room air 32 w over evaporator coil 30 c to produce cooled dehumidified room air 32 c which is expelled back into the room by blower 30. Warm room air 32 w may also lose some moisture that is condensed in evaporator coil 30 c and is collected in condensed water collection pan 30 d as described in FIG. 3.

Similarly, operation of blower 40 induces outside air 42 c over condenser coil 40 c to produce warmed outside air 42 w which is expelled back to the outside environment by blower 40.

Referring now to FIG. 4, compressor impeller 50 i circulates the refrigerant in a closed loop between condenser coil 40 c, fluid expansion device 50 v, and evaporator coil 30 c by fluid conduits 50 b, 50 c, 50 d and 50 a. Flow conduit 50 b connects fluid outlet 50 q of compressor impeller 50 i to the refrigerant inlet connector of condenser coil 40 c. Flow conduit 50 c connects the refrigerant outlet connector of condenser coil 40 c to the fluid inlet connector of fluid expansion device 50 v. Flow conduit 50 d connects the fluid outlet connector of fluid expansion device 50 v to the refrigerant inlet connector of evaporator coil 30 c. Finally, flow conduit 50 a connects the refrigerant outlet connector of evaporator coil 30 c to fluid inlet 50 p of compressor impeller 50 i to complete the refrigerant flow loop.

The refrigerant is compressed by compressor impeller 50 i to a relatively hot, high-pressure refrigerant 52 r which then passes through the coils of condenser coil 40 c wherein it is condensed to high-pressure, liquid or two-phase refrigerant 52 s. High-pressure liquefied refrigerant 52 s is then passed through fluid expansion device 50 v wherein its pressure is reduced. Fluid expansion device 50 v can be a valve, an orifice, or any other fluid pressure reducing device. The reduction of pressure causes the temperature of liquefied refrigerant 52 s to drop and the refrigerant leaves expansion device 50 v as highly cooled liquefied refrigerant 52 t. Highly cooled liquefied refrigerant 52 t then passes through the coil of evaporator 30 c wherein it absorbs heat from warm room air 32 w and undergoes a phase change into low-pressure gasified refrigerant 52 u. During this heat-exchange process, warm room air 32 w is cooled to cooled room air 32 c. Low-pressure gasified refrigerant 52 u is then returned to impeller 50 i of compressor unit 50 and leaves impeller 50 i as high pressure refrigerant 52 r to repeat the above-described refrigeration cycle.

It will be obvious to persons skilled in the art that CIWAC 10 could also function as a heat pump, denoted in FIGS. 5A and 5B by reference number 10′, by the incorporation of a fluid flow reversing device (FFRD) 50 r. FFRD 50 r can be a 4-port valve or other such flow-reversing device, which is well-known to practitioners of the art. FIG. 5A shows the operation of CIWAC 10′ as an air-conditioner for the cooling of a room while FIG. 5B shows the operation of CIWAC 10′ as a heater for the heating of a room. The design and construction of heat-pumps is well known to practitioners of the art and is described in Mechanical Engineers Handbook, 8^(th) Edition, Chapter 12, FIG. 23, Page 12-107, which is incorporated by reference herein.

In FIGS. 5A and 5B, refrigerant flow conduits 50 a and 50 b are now connected to two ports of FFRD 50 r instead of to fluid inlet 50 p and fluid outlet 50 q of compressor impeller 50 i as shown in FIG. 4. The remaining two ports of FFRD 50 r are connected to additional refrigerant flow conduits 50 e and 50 f. Flow conduit 50 e is connected to fluid inlet 50 p of compressor impeller 50 i. Flow conduit 50 f is connected to fluid outlet 50 q of compressor impeller 50 i. As shown in FIG. 5A, during its operation as an air-conditioner, FFRD 50 r directs low-pressure refrigerant 52 u from conduit 50 a to conduit 50 e and high-pressure refrigerant 52 r from conduit 50 f to conduit 50 b. This operation of CIWAC 10′ follows the operation of CIWAC 10 as a room air-conditioner as shown in FIG. 4. Further, as shown in FIG. 5B, during operation of CIWAC 10′ as a room heater, FFRD 50 r directs high-pressure refrigerant 52 r from conduit 50 f to conduit 50 a and low-pressure refrigerant 52 u from conduit 50 b to conduit 50 e, thereby reversing the direction of flow of the refrigerant in the refrigerant loop. Therefore, condensation of warm high pressure refrigerant 52 r occurs in coil 30 c and evaporation of cold liquefied refrigerant 52 t occurs in coil 40 c resulting in the warming of room air 32 w.

The use of CIWAC 10′ as a heat-pump is claimed herein as falling within the scope of the present invention.

As shown in FIG. 1, casing 20 of CIWAC 10 is designed to not interfere with the fully closed position of window 70 thereby enabling the full closure of sliding windowpane 72 s for additional personal safety. This feature also minimizes the possibility of theft of CIWAC 10 as it can be located entirely inside the room and is not accessible from the outside when the window is fully closed and locked.

To achieve these means, casing 20 is fitted with standard latching/locking means 62, such as a clasp, latch, hook, or other such fastener to engage sliding windowpane 72 s of a standard horizontal-sliding-pane window 70. As an example, latching means 62 of FIG. 1 comprises a horizontally sliding member 62 s that is free to slide within holding brackets 62 b which are attached to side panel 201 of casing 20. In a first engaging position, sliding member 62 s engages a depression within a channel shaped mating member 62 c which is attached to sliding windowpane 72 s, thus locking windowpane 72 s in a partially open position for the operation of CIWAC 10. In a second retracted position, sliding member 62 s disengages the depression within mating member 62 c to allow sliding windowpane 72 s to be slid to a fully closed or fully open position. Thus the installation of CIWAC 10 of the present invention in window 70 does not interfere with the operation of sliding windowsill 72 s, which can be fully or partially opened and closed as desired. The narrow width of CIWAC 10 of the present invention may further discourage burglars from trying to gain entry into the room by removing the WAC.

CIWAC 10 of the present invention can be attached to an inner wall surface, for example, the surface of the lower windowsill 70 s and/or the surface of the inside wall 70 w of the room, by standard fastening means 60 c which could include brackets and screws or other such fasteners. Thus, there is no necessity to cut out an opening in the wall to install CIWAC 10 as may be necessary for conventional WACs. This feature provides for the relatively easy and damage-free installation of CIWAC 10. This installation feature is especially advantageous to a renter who may be liable for causing damage to the premises.

A vertical flexible sliding air-seal 64, which can be attached either to sliding windowsill 72 s or to casing 20, reduces the leakage of outside warm air into the cooled room. Vertical flexible sliding seal 64 can be provided with an adhesive surface for attachment either to sliding windowsill 72 s or to casing 20. As shown in FIG. 1, vertical sliding seal 64 comprises an adhesive-backed base 64 b which is stuck to rear panel 20 z of casing 20. A flexible sealing strip 64 w, which is attached to base 64 b, slidingly contacts the internal windowpane surface of sliding windowpane 72 s to create a relatively air-tight sliding seal there-between. Sealing strip 64 w can be configured as a flexible wiper blade (similar to an automobile windshield wiper-blade) or a flexible brush strip (similar to that used in rotating doors). As an alternative to the previously described sliding seal arrangement, it will be obvious that adhesive-backed base 64 b could instead be attached to windowpane 72 s and sealing strip 64 w could instead contact rear panel 20 z.

A dimensionally adjustable profile plate 60 x is provided to close off the unobstructed portion of the window opening that is not covered by rear panel 20 z of casing 20. Profile plate 60 x can be made of an easily-cut Styrofoam or plastic sheet to facilitating fitting into windows of differing dimensions. Profile plate 60 x reduces the leakage of outside warm air into the cooled room. Profile plate 60 x is attached to casing 20 and right windowsill 70 r and top windowsill 70 t by suitable fastening means such as screw-on brackets 60 y and/or stick-on brackets 60 u.

Height-adjustable support pedestals 66 help support CIWAC 10 from the floor. As shown in FIG. 1, each pedestal 66 comprises an exterior steel-tube 66 y with feet 66 b, an interior telescoping steel-tube 66 x which slides within exterior tube 66 y, and a locking screw 66 s to lock interior tube 66 x at the required height within exterior tube 66 y. Yet other materials of construction, for example, rigid plastics, and configurations of height-adjustable pedestals will be obvious to one of skill in the art.

To reduce manufacturing costs, conventional WACs can easily be modified to the CIWACs of the present invention. For example, a Samsung™ WAC, model AW0505M has overall external dimensions of 16.75 inches wide×12.25 inches high×13.5 inches deep. The manufacturer states that this model has a cooling capacity of 5,200 BTUH and is suitable for cooling a 10-ft×15-ft room. The evaporator coil has face-area dimensions of approximately 15 inches wide×9 inches high and is approximately 1.5 inches deep. The condenser coil has face-area dimensions of approximately 16 inches wide×12 inches high and is approximately 1.5 inches deep. The compressor dimensions are approximately 4 inches diameter×11 inches high. Changing the evaporator coil face-area to 8 inches wide×17 inches high while maintaining the 1.5 inches depth provides equal face and heat transfer area to maintain the same cooling capacity. Similarly, changing the condenser coil face-area to 8 inches wide×24 inches high while maintaining the 1.5 inches depth provides equal face and heat transfer area to maintain the same cooling capacity. Alternately, the evaporator coil face-area can be 6 inches wide×22.7 inches high and the condenser coil face-area can be 6 inches wide×32 inches high for an equivalent cooling capacity.

As another example, a Whirlpool™ model ACQ158XR has approximate overall external dimensions of 25 inches wide×16 inches high. The manufacturer states that this model has a cooling capacity of 15,000 BTUH. The evaporator coil has face-area dimensions of approximately 24 inches wide×13 inches high. The condenser coil has face-area dimensions of approximately 24 inches wide×15 inches high. Changing the evaporator coil face-area to 18 inches wide×18 inches high while maintaining the same coil-depth provides equal face and heat transfer area to maintain the same cooling capacity. Similarly, changing the condenser coil face-area to 18 inches wide×20 inches high while maintaining the same coil-depth provides equal face and heat transfer area to maintain the same cooling capacity. Thus the existing cooling capacity can be maintained within the new user-friendly configuration with little engineering effort or additional cost. It will be obvious that different dimensions will apply for other different cooling capacities of WACs. Depending on the cooling capacity of CIWAC 10 and the required physical configuration, it is contemplated that the width of CIWAC 10 could therefore vary between 6 to 24 inches.

Other refinements to the above design could be incorporated to improve the operational characteristics and aesthetics of CIWAC 10. For example, as shown in FIG. 6, an electronic noise cancellation system (ENCS) 80 can be provided with CIWAC 10 to reduce audible noise 10 n generated by CIWAC 10 during its operation. Electronic noise cancellation systems are well known in the electronics art. ENCS 80 comprises a microphone 82 or other such audio-input device for inputting audible noise 10 n generated by CIWAC 10 to ENCS 80. Microphone 82 generates an electrical wave-form 82 s which is inputted by connecting wires 82 w to an electronics circuit 84 for generating an opposite phase electrical wave-form 84 s. Electronics circuit 84 outputs opposite phase electrical wave-form 84 s through connecting wires 84 w to electrical speaker 86 or other such noise-generation device. Speaker 86 generates opposite phase noise 80 n to reduce audible noise 10 n that is generated by CIWAC 10. It will be obvious that other configurations of noise cancellation systems could also be used to produce the same noise reduction results. It will be quite obvious that ENCS 80 could be used with any WAC regardless of its physical configuration. Thus, the use of ENCS 80 with other WAC designs, besides CIWAC 10 described herein, is considered to fall within the scope of the present invention.

It should also be apparent to those skilled in the art that modifications may be made to the embodiment described above without departing from the spirit or scope of the invention. For example, the dimensions given in relation to the preferred embodiment are preferments only and could easily be varied to suit different wall and windowsill thicknesses and different capacity air-conditioners. Further, casing 20 could also be box-shaped without notch 20 c to fit taller windows. Yet further, fastening means 60 c may take many different forms from those shown herein. While blower 30 and 40 are shown operated with individual blower motors 30 m and 40 m respectively, a single blower motor which rotates both blowers 30 and 40 can also be used without departing from the spirit of the invention.

Whilst none of the electrical connections are shown, clearly the CIWAC may incorporate appropriate switches, one or more thermocouples, and one or more thermostats to control its operation. All of these variations and modifications are considered to fall within the scope of the present invention. Accordingly, it is intended that the invention be limited only by the spirit and scope of the following claims. 

1-20. (canceled) 21) A Compact Internal Window Air Conditioner (CIWAC) for installation on the internal windowsill of a horizontally-sliding-pane window, the CIWAC comprising a casing and a closed-circuit vapor-compression refrigeration system located within the casing, the casing having a narrow face-width and an elongated face-height, the aspect ratio “H/W” of face-height “H” to face-width “W” being greater than 3.5, the face-width dimension “W” being 10 inches or less, an indoors-facing wall of the casing having openings for circulation of the room air through the evaporator coil, an outdoors-facing wall of the casing having openings for circulation of the outside air through the condenser coil, further characterized in that the casing is adapted to be mounted totally inside the room on the inside windowsill of the horizontally-sliding-pane window without protruding through the window-frame or wall, the lower end of the casing having a means to engage the inside lower-sill of the window-frame, the casing being supported by the inside lower-sill of the window-frame. 22) The Compact Internal Window Air Conditioner of claim 21, wherein the means to engage the inside lower-sill of the window-frame is an inside corner in the lower wall of the casing. 23) The Compact Internal Window Air Conditioner of claim 21, further characterized in that the casing of the Compact Internal Window Air Conditioner does not interfere with the opening or closing of the sliding windowpane of the horizontally-sliding-pane window. 24) The Compact Internal Window Air Conditioner of claim 23, further comprising flexible air-seals on the casing, the flexible air-seals slidingly contacting the inside surface of the windowpane of the horizontally-sliding-pane window. 25) The Compact Internal Window Air Conditioner of claim 23, further comprising flexible air-seals which are installed on the inside surface of the windowpane of the horizontally-sliding-pane window, the flexible air-seals slidingly contacting the rear panel of the casing of the Compact Internal Window Air Conditioner. 26) The Compact Internal Window Air Conditioner of claim 23, further comprising a pedestal for supporting the Compact Internal Window Air Conditioner's casing from the floor. 27) The Compact Internal Window Air Conditioner of claim 26, wherein the pedestal is height-adjustable. 28) The Compact Internal Window Air Conditioner of claim 21, further comprising a fastener for attaching the Compact Internal Window Air Conditioner's casing to an inside wall surface of the room. 29) The Compact Internal Window Air Conditioner of claim 27, further comprising a fastener for attaching the Compact Internal Window Air Conditioner's casing to an inside wall surface of the room. 30) The Compact Internal Window Air Conditioner of claim 21, characterized in that, the intake and outlet openings for the cooling air for the refrigerant condenser coil flows are both located on the rear panel of the casing of the Compact Internal Window Air Conditioner. 31) The Compact Internal Window Air Conditioner of claim 21, characterized in that condensed water is collected from the evaporator coil and used to cool the refrigerant condenser coil. 32) The Compact Internal Window Air Conditioner of claim 31 wherein the condensed water is sprayed on the refrigerant condenser coil. 33) The Compact Internal Window Air Conditioner of claim 21, further comprising a refrigerant flow reversing means to enable the operation of the Compact Internal Window Air Conditioner as a heat-pump. 34) The Compact Internal Window Air Conditioner of claim 21, further comprising an electronic noise cancellation system for reducing the noise generated during the operation of the Compact Internal Window Air Conditioner. 